On 07/05/2012 19:16, Bob Eager wrote:
On Mon, 07 May 2012 19:03:48 +0100, dennis@home wrote:

"John wrote in message
o.uk...
On 06/05/2012 22:09, dennis@home wrote:


"Bob wrote in message
...
On Sun, 06 May 2012 20:14:49 +0100, dennis@home wrote:

"Bob wrote in message
...

The point is, however, that modern disks have enough time, on a
powerfail, to retract the heads before the cushion fails.

Modern disks don't retract the heads like the old ones did. The old
ones
had ramps which the head carriers went up when the heads retracted,
this
removed them from the surface. Modern ones land on the disk surface,
they retract to a "safe" landing zone.

Of course, dennis. Just like the latest WD Caviar Black, which uses
ramp load.

That's one of the latest ones with shock protection isn't it? Not all
have that.

and yet a sentence earlier, you claimed that "Modern disks don't
retract the heads"... Does this not cause you cognitive dissonance?

No, why would it.
Anyway its easy to wriggle out of as you would have to prove no modern
disks land their heads to show what I said was actually untrue. However
you can read whatever you like into what I said even if you have to
stretch it to the limit.
I did actually forget that they have reintroduced the ramps on some
mobile disks as part of the shock protection.

The Caviar Black is not a mobile disk, though. And that has ramps.

Indeed...

The Green and Blue desktop 3.5" drives use the same arrangement

Nice clear view of them in here from about 1:27 on:

http://www.youtube.com/watch?v=uR1RO...feature=relmfu

Also good shot of the same arrangement on a Hitachi Deskstar:

http://www.youtube.com/watch?v=zGIaD9sNEWE

Contrast that with the on disk parking arrangement used by Seagate:

http://www.youtube.com/watch?v=3KwYO...eature=related


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/